WD Gaster
by Whalecat
Summary: Papyrus went comatose, and Sans doesn't know what to do, until he hears from something that Doctor Alphys, the royal scientist, is working on a cure. What will happen, I wonder? Enjoy, my darlings.
1. Fallen Down

**Yes, yes, I should be working on Lies Over Truth, but I have so many story ideas**

 **I apologize so much (not really, this is a good story idea)**

 **enjoy children because i did**

Sans was absolutely terrified.

Papyrus didn't wake up today. He didn't wake up yesterday, either. They had both heard about the monsters that were falling down, but.. Why wasn't it me? Sans wondered, staring at Papyrus, tears falling onto the red scarf. There had to be a way to save him, it couldn't just be like this forever, Sans awake, Papyrus forever asleep. It didn't make sense. Why was this happening? Was it due to another timeline? If that were the case, why wasn't everyone comatose?

Nothing was making sense. Why would anyone fall down? It shouldn't have been happening at all, even if it was happening in all of the timelines. It made Sans angry. He almost did something.. cowardly. But, he gave the scarf back to Papyrus.

He, formally being a scientist before Alphys became the royal scientist, attempted to figure out a way to wake Papyrus back up. First, he joked around, making all of the horrible skeleton puns he could ever make. It didn't work. Then, he went to the scientific part, trying to come up with a solution, an injection maybe, that could be directly put into the soul.

Nothing he did worked.

Then, after a long week, while walking through Snowdin and Waterfall, he heard information from someone.. something. Doctor Alphys, the royal scientist, was apparently working on a cure for the monsters that went comatose. _I-I can save him! Papyrus, you're going to be okay!_ For once, in a long, long time, Sans was relieved, crying of joy.

But, for some reason, Sans couldn't help but stay back, and not immediately rush to Alphys's aid. He stayed there for a few days, waiting. "I-If this is a joke, Pap, it's not funny. You don't make jokes like this."

Then, while walking again, he heard from the same voice, in Waterfall this time. Doctor Alphys was working on an injection, as well, and she finally found a solution. It felt as if a weight was lifted off Sans's shoulders. He rushed back to Snowdin, picked up his phone, and called up the Doctor.

"U-Uh, hello? Wh.. How did you get this n-number?" The stuttering voice was so familiar to Sans, but it still sounded different. _Probably from all of the stress_ , Sans thought.

"Hey, uh, Alphys. It's Sans. This is pretty urgent, so sorry if I'm interrupting on anything," Sans quickly paused to pick up Papyrus. He ignored the weight of his brother, and began to walk outside of his house. "I, uh, something's really wrong. It's been a few weeks and I tried to think up somethin' to make it work, but nothing happened. I'm losing my science touch. Heh.." He was already to Waterfall.

"S-Sans? A.. C-calm d-down. What's wrong? A-Are you and your brother o-okay?" Alphys's voice cracked, but she ignored it, waiting for the reply. It came quickly.

"That's.. the thing." Sans was glad the flying duck was on his side today, and it flew him over to the over side. "I.. huff.. Papyrus.. ain't doing too.. huff.. well.." The skeleton tried to adjust his grip on the phone, but just didn't care.

"Wh-what do you mean by... 'not doing so well'?" There was a silence on the other end, until finally, "O-oh god. Oh no. I-Is he okay? Please.. tell me he's-"

"I heard that you had a solution to all of the monsters that went and fell down."

"Wh-what? How did you-" Alphys interrupted herself, but quickly continued, "W-well, yes, I am working on a solution, but-"

"Oh, thank god.. As long as I'm not.. huff.. interrupting anything on your.. schedule.. Can I.. uh.. get your help?" Sans panted, walking to the laboratory right in front of him. It took shorter than expected to get there. No wonder he was so tired.

"Well.. yeah, I'm open." She paused the episode of Mew Mew Kissy Cutie 2, sort of glad she didn't have to watch it anymore. "Where are y-you?"

"Alphys.. ALPHYS!" Sans slammed his free hand on the door, and heard a robotic voice, a reply from Alphys, then the door opened with Undernet's sensation, Mettaton. "Sans, darling, hand me Papyrus, please." The robot calmly said, extending both of his hands, and, after a few seconds of tension, Sans finally gave up, giving his brother to the famous robot. "Thank you. Alphys! Sans is here with his.. brother!"

"Wh-What!? Here already!?" Alphys thought it was someone else at the door, but quickly rushed down to greet Sans. She rushed to the road leading downstairs, but quickly regretted the feat, as she saw.. "Oh.. o-oh god, Sans, how long?"

"Week. Been like that for a week. I tried to cook up a solution to this, but it never worked." Sans mumbled. "You see what I mean by urgent? I- I need you to help him. I know I'm usually a funny guy, but I'm.. I'm bein' serious, here. I know that you're doing something, you need to help him- You need to help me.. Please-"

"N-no."

The silence in the laboratory was almost deafening. A single word caused all of this silence, because Alphys knew that the experiments wouldn't work on Papyrus. If she did anything, like inject Determination into his soul, it wouldn't work. The Royal Scientist looked away as tears began to fall out of Sans's eyesockets. Then, after almost five minutes of deathly silence, Sans went into a fiery blue rage.

 **"if YoU don't helP, then i'll do it mYSelf.."** Sans's eyes flashed blue, and the labratory became a bigger mess than it already was. "S-Sans, stop! I- You don't know what you're doing!" Alphys screamed at the top of her lungs, while Mettaton was thrown into the tornado of a mess. Even his weight couldn't withstand Sans's rage. **"wheRe iS it!? i know YoU have some sort of-"**

That was all Alphys had heard, until she ran back up to her room. Sans, fortunately, was looking in the wrong places. _I'm sorry Sans, but you can't save Papyrus, yet.. I need to hide the injections.. Damn it.. Where? I.. I don't have much time until he comes up here... and Mettaton.._ She could easily hear all of the commotion going downstairs.

Mettaton's voice, Sans screaming, tearing of important documents and papers, the screen which showed her all of the cameras hooked up around the Underground, and all of the other things flying everywhere. Alphys knew she didn't have enough time. Since Sans was such a quick searcher, and there wasn't much stuff down there, it wouldn't be much more until he finally got up to her room.

 **"alphYYYYYSSSSSS.."** Sans echoed through the laboratory, and, before Alphys could react, since all of the injections were in a suitcase she was holding, tried to hide the case again. **"i knew YoU had something."** Sans's grin widened, as he threw himself up to her room, flinging the suitcase out of Alphys's arms.

"Sans! N-No, you can't.. Don't use the injections! I- They WON'T work!" The scientist screamed, but Sans couldn't hear her. He rushed back down to where Papyrus was laying, and forcefully opened the suitcase.

 **"P-PAP, we'Re fine, YoUR'e going to be okaY."** Sans murmured, ripping his brother's shirt open in a panic. Papyrus's soul was a fiery orange, the complete opposite of Sans's soul, which was an ice cold blue. Taking one of the syringes, he inserted it into Papyrus's soul.

"S-Sans, no.. Why did you- It.."

"I'm not letting Papyrus go alone." Sans mumbled, lifting up his own shirt. He took another one of the needles, and shoved it into his soul. He only grunted in pain, almost stopping when he felt the liquid forced into his soul.

"A.. Oh.. God.. N-no.. S-Sans, you knew that i-it.. b-but you s-still.." Alphys stuttered. There was no reply. "S-Sans? H-how are you.. feeling?"

"I.. a little weird, shaky, but I'm okay. I think." Sans looked away from his brother, up to Alphys. "What was that stuff?"

"D-Determination. It's the thing that keeps human souls persisting after death. I.. there.. I created.. I, uh.. found a way to re-create it... Oh.. god. Where's Mettaton!?" Alphys panicked, but only momentarily, until there was someone behind her, black hair(?), fancy outfit, arms..

Legs.

"M-Mettaton!? Oh.. n-no, your switch got turned again." Alphys stuttered, trying to get the robot to turn around.

"Alphys, darling, I'm fine. It's the perfect opportunity to see how the new body is working, anyways." Mettaton hummed, smiling. But his eye quickly widened in surprise, and his smile turned into a straight face. "Sans.. my dear.. you should turn around."

"Wowie! Is THAT Mettaton!? I can't believe I'm meeting THE Mettaton!"

 **MY HEART IS HURTING. VERY BADLY.**

 **Also, if you got it, good job, I only capitalized the letters in Papyrus's name ;D**

 **Next chapter soon(?)**

 **Don't think about it much, like Undertale's Hard mode.**


	2. Fusing

**MY HEART AND MY SOUL IS IN PAIN**

 **GOSH, JUST PLEASE ENJOY THIS STORY**

Everyone's attention snapped back to Papyrus, and, almost immediately, Sans wrapped his arms around his brother. "P-Pap.. you're.. okay..?" Sans mumbled, already sobbing. Papyrus looked confused, as if he just woke up from a good night's rest. He, of course, didn't ask about how he ended up in the royal scientist's laboratory, and why Mettaton was so changed. His favorite sexy rectangle looked even better, though.

"What? You shouldn't be asking this question, Sans, I should! You're crying a river, what happened?" Papyrus put his arms around his brother, and Mettaton stepped back, pulling Alphys with him, so they could spectate the commotion from far away. The two ignored the conversation of the brothers, since they thought it was a private moment for them, and started one of their own.

"Mettaton, w-wait! What if -"

"'What if' nothing, Alphys. You have a lot of explaining to do. What happened to them? That injection.. 'Determination', you called it? Why did you keep it a secret from me? It works, doesn't it?" The robot crossed his arms, and Alphys sighed.

"I- I hope so. But.. They.. They'll be f-fine!" Alphys mumbled, smiling, but she was panicking on the inside. _The Determinjection won't work. Did they use the prototypes? Did they use the actual injections? Oh, god, this is my fault.. They're going to become just like the others, and it's going to be my fault.. What will.. Undyne.. How will she react to this? Eheh.. I can already imagine the conversation.._

 _"Hey, Al! Do you know where Papyrus went? I'm starting to get worried, 'cause he's not showing up to any of his lessons. And he's not picking up his phone.. I've already called ten times. He never picked up." Undyne sighed, although she didn't look angry, but she looked like she was close to tears. Worried._

 _"P-P- Papyrus?! No.. nonono.. Nope! I.. uh.. have seen- HAVEN'T seen him!" Alphys lied. It was her fault. All of this was her fault, no matter what she could do, it felt horrible lying to Undyne. "Oh, who am I kidding.." the scientist sighed. She explained what she was doing with all of the monsters that had fallen down, and the Determination Injections were supposed to make their souls persist after death when they died. "B-But.. none of them d-died. They just.. They woke up! Then.. then.. There was a day when Sans came in with Papyrus. He.. Papyrus had, uh.. fallen. Down."_

 _Undyne just stared at Alphys, at first. "You.. you injected him?"_

 _"No, it wasn't-"_

 _"Alphys. I thought we were friends. But I don't even know you." Undyne walked away, and Alphys was screaming as loud as she possibly could, her throat already in pain. "Undyne! W-wait, it wasn't.. it.. wasn't.. me.. Please.. come back.. I'll do anything t-to make you come back! I.. I.. love.. you.." She sobbed, falling to her knees. Alphys didn't even try to follow Undyne. Suddenly, Undyne, in her full set of armor, was in front of Alphys. She leaned down, put her hand on Alphys's shoulder, and said,_

 _"I know what you can do to make it up to me." She whispered. Before Alphys could react, there was a spear right were her soul was. "Die."_

Alphys snapped back to reality, when Mettaton shook her shoulder hard enough. "Doctor Alphys? You're crying. What happened?" Mettaton asked, and Alphys immediately went to wipe the tears away. "N-n-noth..ing! Nothing.. a-at all. Just happy for Sans and Papyrus." She lied.

The two brothers, Sans and Papyrus, talked with each other for a while since, by Alphys's orders, they had to stay in the laboratory. The two laughed, cried, and Sans filled his brother in on what happened. "What!? I fell down? What exactly did the Great Papyrus do in order for that to happen?"

"Dunno, bro, but at least you're okay now." Sans replied. It seemed as if everything was okay. Everything was fine. To Alphys, it was a huge relief, since she was afraid that Sans would have a horrible reaction to it, because he never went comatose.

Finally, after a few minutes of arguing, Sans and Papyrus were given the permission to leave.

The melting process began almost immediately.

"S-Sans, you're sweating quite a lot.. It looks like you're melting.." Papyrus stopped Sans from exiting the laboratory. "Oh. Sans. You.. are melting. Oh MY GOD, SANS YOU'RE MELTING, ARE YOU OKAY!?"

"B-Bro.. You're.. like that.. too." Sans mumbled, staring up at Papyrus, almost barely. He was almost down to Sans's height. They embraced each other, crying.

"W-Well, whatever happens.. I love you, brother."

"I.. I love you, t-too.. bro."

"M-Mettaton, go back upstairs! I-I need.. I have to lock the doors, go!" Alphys ordered, running up the stairs as she heard the screaming of the two skeleton brothers. "They're fusing. METTATON!?" Alphys screamed over the cries of agony and pain from Sans and Papyrus.

"I-I'm right behind you, darling. Close the doors.. please." Mettaton murmured, and the royal scientist, slammed the buttons down. "God, I'm glad I installed cameras here.." She mumbled, turning on her computer. It was quite dark in the room below her, but she almost immediately saw the.. thing that was down there. They were standing- Standing!? Standing.. right in front of the door, staring right at the camera that Alphys was looking through to see them. She turned to another camera. They looked there, too.

She tried something else. Alphys moved her computer screen to a camera outside her laboratory. A secluded one in Snowdin.

They were there. How was that possible? They moved too quickly, and.. they looked so familiar. But the amalgamate was too far away in order for her to see them in detail.

 _ **"Alphys."**_ An unfamiliar voice said, and she screamed, hiding under her desk. "N-No! Nononononono.. God, I'm so sorry, I-I didn't mean.. I didn't want.. I don't.. Don't hurt me.."

 **"Al..ph..ys..?"** Sans asked, leaning down to look at the Royal Scientist. _"Why are.. you so af..raid? I-I am tr..uly sorry for.. scaring you."_ Papyrus mumbled, reaching out to comfort Alphys, but stopped when they saw that.. There were holes in their hand. ** _"Gh- Wh.. AAAAAAAGH! m.. mY voicE.. iT huRTS.."_** Papyrus and Sans stepped back, falling onto the floor. _Wh.. What is this!? SANS!?_ **P..Papyrus? Oh, god.. What's happening?** _I.. I don't know, Sans. But how are we speaking?_ **I dunno, b-bro, but I-I'm freakin' out..** _W-Well, Sans, just try to stay calm! We.. We'll be alright._ **Pap.. I don't.. We're in the same body.** _Wait. WHAT!? HOW? WHEN!? WHAT.._ **We just.. I can't.. but we're in the same body.**

"G-Gaster?! Y-You're the previous Royal Scientist, why are you-"

And then, the shocking revelation. "Oh. Oh my god. I.. I made W.D. Gaster.. Sans, Papyrus? You can't speak. This may be familiar to you, and I'm probably a little rusty, b-but.." Alphys continued to make hand motions, and the fused being in front of her that looked like the previous scientist, Gaster, immediately recognized the motions. He replied without thinking.

'What's happening to me? What happened to Sans and Papyrus? Are we in the same body? How?' They motioned quickly, and Alphys almost barely understood. "I- I need you to go to a different timeline." She spoke quickly. "You can't stay here, Gaster. Go to a timeline far, far back. You'll be okay there."

'T-Timeline? What are you talking about? I can't leave! I have to talk to Undyne..? Who's Undyne? Where am I? Who are you?' Gaster looked angry while motioning his thoughts.

"Go to a different timeline. Please." Alphys murmured, and W.D. Gaster immediately followed her words, moving to a separate timeline. Sans and Papyrus were forgotten in his body.

But he had a feeling that he had to save one of them. Someone-

Gaster regretted thinking while travelling through time and space, since he didn't make the landing while falling into one of the timelines he wanted. _This isn't the one._. He thought, confused.

"Sans! Sans! Someone just fell! Exscuse me, sir? Are you okay?" A small, skeleton child asked Gaster, and he immediately stepped back, cleaning his gray coat and white pants off. There was no need to use hand motions, here. The small child wouldn't understand. So, Gaster just nodded.

"Papyrus, I told you not to run off like that!" Another child, Gaster assumed was Sans, ran up to his younger brother- Papyrus, was it?- and paused, looking up at Gaster. "..Whoa. Sorry if my bro was doing something to you. We'll.. uh.. go." The two brothers turned to walk away.

"Gh- Wait!" Gaster managed to say, in an older version of Sans's voice, but it was a mix of the two brothers.

 **Why did I stop here, i don't know**

 **next chapter soon? I guess?**

 **Also surprise i guess**

 **Gaster= Papyrus+Sans?**


End file.
